Heat removal is a prominent factor in a computer system and data center design. The number of high performance electronics components such as high performance processors packaged inside servers has steadily increased, thereby increasing the amount of heat generated and dissipated during the ordinary operations of the servers. The reliability of servers used within a data center decreases if the environment in which they operate is permitted to increase in temperature over time. Maintaining a proper thermal environment is critical for normal operations of these servers in data centers, as well as the server performance and lifetime. It requires more effective and efficient heat removal solutions especially in the cases of cooling these high performance servers.
Power intensive processors enable the solution of intensive computing such as deep learning. Electrical servers having those processors, i.e., high-power central processing units (CPUs) and/or general-purpose or graphical processing units (GPUs), have a very high power density per volumetric space. Liquid cooling is a proper thermal management solution for high power density.
In liquid cooling, a manifold is used for distributing and regulating fluid with main inlet/outlet ports and fluid sub-ports. The main inlet and outlet are connected to external cooling source, and the sub ports are connected with either server loops or cooling device loops. The fluid distribution manifold is a mature technology; however, most of the conventional manifold designs are not efficient in some application scenarios.
A common design is to have a supply manifold and a return manifold mechanically combined as one unit. However they are not thermally connected. For example, in a server level application (e.g., server level manifold), when there are multiple loops used in one server module, if the supply and return manifolds are not directly connected, the server level manifold needs to connect the liquid from the electronic rack and return the liquid back to the electronic rack. However, the liquid travels a long path, fluid pressure drop becomes higher, and the numbers of connectors and connection points increase and thus, the reliability decreases.